1. Field of the Invention
A known goal or object of the introduction of fluids or liquids, especially of water, into the combustion chamber of engines operated with fluid or liquid fuels, is to reduce the nitrogen oxide or nitric oxide concentration in the exhaust gas by lowering of the process temperature level. The knock inclination or tendency with employment of fuels of nominal or small anti-knock resistance beyond that can be controlled by means of water introduction.
2. Description of the Prior Art
Introduction of water or alcohol into the combustion chamber of such engines is a means for reduction of the NO.sub.x -emission of internal combustion engines known and tested for a long time. There was already shown repeatedly, that as far as to a predetermined fluid or liquid quantity or volume no negative consequences or effects upon the behavior of the efficiency, effectiveness or output are ascertainable or detectable.
The nitric oxide formation or development during the combustion is determined essentially by the combustion temperature and also can be reduced by the admixing of inert components, ingredients or constituents to the charge. The inert charge components or constituents, corresponding to the specific thermal or calorific capacity or heat-absorption capacity, with fluid or liquid materials additionally corresponding to the heat of vaporization or latent heat of evaporation thereof, can take up a considerable proportion of the heat released during the motor, motive or kinetic process and thus lowering or decreasing the process temperatures.
As methods or procedure for introduction of fluid or liquid with engines driven or operated with fluid or liquid fuels there are known today on the one hand the addition of fluid or liquid to the combustion air supplied to the engine before or ahead of the combustion or operating chamber of the engine and on the other hand there is known the high pressure injection of the fluid or liquid into the combustion chamber. With the first method, which is also called suction-tube addition or manifold injection because of the most frequently employed location of the fluid or liquid addition, the fluid or liquid is injected continuously at a low pressure into the combustion air flow or stream or also is injected intermittently via a central jet or nozzle, or also via several individual jets or nozzles. In order thereby to obtain a homogeneous distribution of the fluid or liquid in the combustion air, the injection jets or nozzles must finely atomize the fluid or liquid. The small jet or nozzle cross sections necessary for doing so bring forth high requirements as to contamination with respect to the preparation of the fluid or liquid to be injected and with water with respect to the hardness of the water. Additionally, there cannot be precluded the partial separation of fluids or liquids on the suction-tube walls with all damaging consequences with the suction-tube addition of fluid or liquid.
With the manifold injection of the fluids or liquids, there is not assured a good atomization of the fluid or liquid because low flow rates or speeds arise or occur during suctioning of the mixture with respect to or giving consideration to the high cylinder filling.
A pre-vaporization of the fluid or liquid and the subsequent admixing to the suction air is connected with problems with respect to an exact dosing of the admixed fluid or liquid quantities or volume. Additionally, there is non-applicable or lost the chance thereby for employment or utilization of the vaporization enthalpy of the fluid or liquid for decreasing or lowering of the process temperature level.
The fluid or liquid medium is injected directly into the combustion chamber by means of a high pressure injection mechanism or equipment with the high pressure injection of fluid or liquid. If the motor is equipped with the Diesel injection system, so the fluid or liquid together with the Diesel fuel can be injected in the form of an emulsion. With that the dosing of the fluid or liquid as well as the production and maintaining of the emulsion must be assured or accounted for by high technical cost. Additionally, there must be provided suitable features or measures to avoid or preclude corrosion damage to the injection system.
Likewise there arises a great cost during utilization, employment or installation of a separate high pressure injection system for the fluid or liquid injection. In each case, there is required also a suitable or adapted preparation of the fluid or liquid also with these methods or procedures.
The known methods for an admixing of a fluid or liquid medium to engines driven or operated with liquid fuels cannot be transferred in a simple manner onto gas engines, since these are provided for especially high service life and all known methods, for example for water admixing, considerably reduce the life expectancy and the disturbance-free operation of the engines. This could not be accepted in view of or with respect to the field of employment of gas engines, so that up to now the employment of the foregoing described introduction of water or alcohol into the combustion chamber on these specific engines was avoided by the experts or average man skilled in the art.